Pre-calculate the set of wrapXArray methods in Definitions

Author: Abel Nieto

compiler/src/dotty/tools/dotc/core/Definitions.scala

@@ -9,6 +9,7 @@ import scala.collection.{ mutable, immutable }
 import PartialFunction._
 import collection.mutable
 import util.common.alwaysZero
+import dotty.tools.dotc.transform.TreeGen
 
 object Definitions {
 
@@ -338,6 +339,12 @@ class Definitions {
     def Predef_classOf(implicit ctx: Context) = Predef_classOfR.symbol
     lazy val Predef_undefinedR = ScalaPredefModule.requiredMethodRef("???")
     def Predef_undefined(implicit ctx: Context) = Predef_undefinedR.symbol
+    // The set of all wrap{X, Ref}Array methods, where X is a value type
+    lazy val Predef_wrapArrayR: Set[TermRef] = {
+      val methodNames = ScalaValueTypes.map(TreeGen.wrapArrayMethodName) + nme.wrapRefArray
+      methodNames.map(ScalaPredefModule.requiredMethodRef).toSet
+    }
+    def Predef_wrapArray(implicit ctx: Context): Set[Symbol] = Predef_wrapArrayR.map(_.symbol)
 
   lazy val ScalaRuntimeModuleRef = ctx.requiredModuleRef("scala.runtime.ScalaRunTime")
   def ScalaRuntimeModule(implicit ctx: Context) = ScalaRuntimeModuleRef.symbol

compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala

@@ -94,7 +94,7 @@ class ElimRepeated extends MiniPhase with InfoTransformer { thisPhase =>
   private def seqToArray(tree: Tree, pt: Type)(implicit ctx: Context): Tree = tree match {
     case SeqLiteral(elems, elemtpt) =>
       JavaSeqLiteral(elems, elemtpt)
-    case app@Apply(fun, args) if isWrappedArray(app) => // rewrite a call to `wrapXArray(arr)` to `arr`
+    case app@Apply(fun, args) if defn.Predef_wrapArray.contains(fun.symbol) => // rewrite a call to `wrapXArray(arr)` to `arr`
       args.head
     case _ =>
       val elemType = tree.tpe.elemType
@@ -108,14 +108,6 @@ class ElimRepeated extends MiniPhase with InfoTransformer { thisPhase =>
           // Because of phantomclasses, the Java array's type might not conform to the return type
   }
 
-  /** Determines whether `tree` is a method call to Predef.wrapXArray */
-  private def isWrappedArray(tree: Apply)(implicit ctx: Context): Boolean = {
-    val elemTpe = tree.tpe.elemType
-    val wrapMethodName = TreeGen.wrapArrayMethodName(elemTpe)
-    val wrapMethodSym = defn.ScalaPredefModuleRef.denot.requiredMethod(wrapMethodName)
-    tree.fun.symbol == wrapMethodSym
-  }
-
   override def transformTypeApply(tree: TypeApply)(implicit ctx: Context): Tree =
     transformTypeOfTree(tree)